A microseismic statistical method for determining the risk range of advanced impact on working faces

Abstract

A microseismic statistical method for determining the range of the working face's advanced impact hazard includes the following steps: using a mine microseismic monitoring system to collect natural microseismic signals during the working face's mining process and determine the source location and energy; selecting an arbitrary coordinate point on the mining project plan as the coordinate origin of a new coordinate system, drawing the new coordinate system, introducing microseismic data, and using a coordinate conversion formula to obtain the coordinates of the microseismic event in the new coordinate system, thereby obtaining the horizontal coordinate of the working face's daily advance position in the new coordinate system; determining the distance of each daily microseismic event from the working face's advance position; counting microseismic events in the area before and after the advance position, dividing the statistical area into equally spaced regions, counting the total microseismic energy and frequency within each region, drawing a curve chart of the change in total microseismic energy and frequency, and classifying the microseismic total energy and frequency hazard levels to determine the range of the advanced impact hazard area. This method can determine the range of areas with advanced impact hazard during working face mining, and is highly reliable and easy to operate.

Description

Technical Field

[0001] The invention relates to a microseismic statistical method for determining a dangerous range of advance impact of a working face, and belongs to the technical field of safe mining of coal mines. Background Art

[0002] Microseismic monitoring, a cutting-edge technology for monitoring and forecasting dynamic hazards such as rock burst, records the vibration spectrum of mining activities to determine and analyze the location and energy of these vibrations. As mining depths increase, the impact of coal and rock dynamic hazards on mine safety and production becomes increasingly prominent. Currently, many mines, particularly those at risk of rock burst and other hazards, have installed microseismic monitoring systems to monitor these microseismic events.

[0003] Most existing microseismic monitoring systems are complex and costly in design, and are unable to accurately monitor the extent of the advance impact danger zone during working face mining. Summary of the Invention

[0004] In response to the problems existing in the above-mentioned prior art, the present invention provides a microseismic statistical method for determining the range of the risk of advance impact on the working face. This method can determine the area range where the risk of advance impact exists during the mining of the working face, and has high reliability, easy operation and low cost.

[0005] To achieve the above-mentioned object, the present invention provides a microseismic statistical method for determining the risk range of advance impact of a working face, comprising the following steps:

[0006] (1) Use the mine microseismic monitoring system to collect natural microseismic signals during the mining process of the working face to determine the source location and source energy;

[0007] (2) Select any coordinate point A(x0, y0) on the plan of the mining project as the origin of the new coordinate system, draw the new coordinate system, and the x-axis of the new coordinate system is parallel to the advancing direction of the working face;

[0008] (3) Introducing microseismic data and processing it through the coordinate transformation formula to obtain the coordinates of the microseismic events in the new coordinate system;

[0009] (4) Determine the starting coordinate B of the working face advancement, introduce the working face footage data, and obtain the x-coordinate of the daily advancement position of the working face in the new coordinate system;

[0010] (5) Determine the strike distance of daily microseismic events from the working face advancement position;

[0011] (6) Divide the statistical areas into equal intervals along the strike direction of the working face, and use the accumulation method to determine the total microseismic energy and microseismic frequency in each statistical area;

[0012] (7) Using the distance from the working face advance position determined in step (5) as the horizontal coordinate and the total microseismic energy and microseismic frequency in each statistical area counted in step (6) as the vertical coordinate, draw a curve of the change of total microseismic energy and microseismic frequency;

[0013] (8) Based on the curves of total microseismic energy and microseismic frequency obtained in step (7), the danger levels of total microseismic energy and microseismic frequency are divided to determine the range of the advanced impact danger zone.

[0014] Furthermore, the method for determining the earthquake source position and earthquake source energy in step (1) is: by installing an SOS microseismic monitoring system in the coal mine, the SOS microseismic monitoring system includes an above-ground acquisition and recording device and multiple single-component probes installed underground, and the multiple single-component probes are installed on the anchor rods of the vertical tunnel floor. The mine microseismic monitoring system is used to collect multiple natural mine earthquake signals during the working face mining process, and each natural mine earthquake signal is processed to obtain its corresponding mine earthquake source position and energy.

[0015] Furthermore, the x-axis of the new coordinate system drawn in step (2) is parallel to the advancing direction of the working surface and has a clockwise angle α with the x-axis of the old coordinate system.

[0016] Furthermore, in step (3), the coordinate conversion formula is:

[0017] x′ ij =(x ij -x o )cos(α)+(y ij -y0)sin(α),

[0018] y′ ij =(y ij -y0)cos(α)-(x ij -x o )sin(α);

[0019] Where x ij 、y ij They represent the x and y coordinates of the j-th microseismic event on the i-th day in the old coordinate system; α represents the clockwise angle between the new coordinate and the x-axis of the old coordinate system; x o y0 and y1 are the x and y coordinates of the origin A of the new coordinate system respectively; x′ ij , y′ ij represents the x and y coordinates of the j-th microseismic event on the i-th day in the new coordinate system.

[0020] Furthermore, in step (4), the x-coordinate of the daily advancement position of the working face in the new coordinate system is determined by selecting the eye B point under the working face as the starting point of the advancement of the working face, introducing the working face footage data, and calculating using the following formula:

[0021] x′ Bi =(x B -x0)cos(α)+(y B -y0)sin(α)±L i ;

[0022] Where x′ Bi represents the advancing position of the working face on day i; x B 、y B L is the coordinate of the selected cutting point B on the working surface; i Indicates the cumulative footage on the i-th day. When the advancement direction of the working face is consistent with the positive direction of the new coordinate x-axis, select "+" for calculation, otherwise select "-" for calculation.

[0023] Furthermore, in step (5), the calculation formula for the strike distance of daily microseismic events from the working face advancement position is as follows:

[0024] d ij =x′ Bi -x′ ij ;

[0025] Where, d ij It represents the strike distance between the jth microseismic event on the i-th day and the advancing position of the working face.

[0026] Furthermore, in step (6), the calculation formulas for the total microseismic energy and the microseismic frequency in each divided statistical area are as follows:

[0027] E n =e 1n +e 2n +e 3n +…+e mn ,

[0028] Q n =q 1n +q 2n +q 3n +…+q mn ;

[0029] Where, E n is the total microseismic energy in each statistical area, i.e., the sub-area; Q n is the frequency of microseismic events in each statistical area, i.e., the sub-area; e in is the energy of the i-th microseismic event in the n-th partition, i = 1, 2, 3, ..., m; q in is the i-th microseismic event in the n-th partition, i = 1, 2, 3, …, m; n is the partition number.

[0030] Furthermore, in step (8), the total microseismic energy and microseismic frequency hazard levels are determined based on the total microseismic energy and microseismic frequency hazard standard values ​​determined by the working face mining conditions and monitoring and early warning indicators.

[0031] The present invention utilizes a mine microseismic monitoring system to collect natural microseismic signals during the working face mining process, determines the source location and source energy, selects an arbitrary coordinate point on a microseismic positioning base map as the coordinate origin of a new coordinate system, draws the new coordinate system, introduces microseismic data, and uses a coordinate conversion formula to obtain the coordinates of the microseismic time in the new coordinate system. The coordinates of the daily working face advance position in the new coordinate system are then obtained, and the strike distance of each daily microseismic event from the working face advance position is determined. Microseismic events in the area before and after the advance position are statistically analyzed, and statistical regions are divided into equally spaced statistical regions. The total microseismic energy and frequency within each statistical region are statistically determined, and a curve chart of the total microseismic energy and frequency is plotted. Based on the obtained curve chart of the total microseismic energy and frequency, the risk levels of the total microseismic energy and frequency are classified to determine the scope of the advanced impact risk area. The present invention determines the scope of the area with advanced impact risk during working face mining, and is highly reliable, easy to operate, and convenient for computer programming. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a schematic diagram of the new coordinate system of the present invention;

[0033] Figure 2 Schematic diagram of the division of statistical areas in an embodiment of the present invention;

[0034] Figure 3 This is a schematic diagram of the working face advancing working state in an embodiment of the present invention;

[0035] Figure 4 3 is a curve diagram of changes in total microseismic energy and microseismic frequency in an embodiment of the present invention. DETAILED DESCRIPTION

[0036] The present invention will be further described below with reference to the accompanying drawings.

[0037] A microseismic statistical method for determining the risk range of advance impact of a working face includes the following steps:

[0038] (1) Use the mine microseismic monitoring system to collect natural microseismic signals during the mining process of the working face to determine the source location and source energy;

[0039] (2) Select any coordinate point A(x0, y0) on the plan of the mining project as the origin of the new coordinate system, draw the new coordinate system, and the x-axis of the new coordinate system is parallel to the advancing direction of the working face;

[0040] (3) Introducing microseismic data and processing it through the coordinate transformation formula to obtain the coordinates of the microseismic events in the new coordinate system;

[0041] (4) Determine the starting coordinate B of the working face advancement, introduce the working face footage data, and obtain the x-coordinate of the daily advancement position of the working face in the new coordinate system;

[0042] (5) Determine the strike distance of daily microseismic events from the working face advancement position;

[0043] (6) Divide the statistical areas into equal intervals along the strike direction of the working face, and use the accumulation method to determine the total microseismic energy and microseismic frequency in each statistical area;

[0044] (7) Using the distance from the working face advance position determined in step (5) as the horizontal coordinate and the total microseismic energy and microseismic frequency in each statistical area counted in step (6) as the vertical coordinate, draw a curve of the change of total microseismic energy and microseismic frequency;

[0045] (8) Based on the curves of total microseismic energy and microseismic frequency obtained in step (7), the danger levels of total microseismic energy and microseismic frequency are divided to determine the range of the advanced impact danger zone.

[0046] As a preferred embodiment of the present invention, the method for determining the source position and source energy in step (1) is: by installing an SOS microseismic monitoring system in a coal mine, the SOS microseismic monitoring system includes an above-ground acquisition and recording device and multiple single-component probes installed underground, and the multiple single-component probes are installed on the anchor rods of the vertical tunnel floor. The mine microseismic monitoring system is used to collect multiple natural mine earthquake signals during the working face mining process, and each natural mine earthquake signal is processed to obtain its corresponding mine earthquake source position and energy.

[0047] As an implementation method, the x-axis of the new coordinate system drawn in step (2) is parallel to the advancing direction of the working surface and has a clockwise angle α with the x-axis of the old coordinate system.

[0048] Specifically, in step (3), the coordinate conversion formula is:

[0049] x′ ij =(x ij -x o )cos(α)+(y ij -y0)sin(α),

[0050] y′ ij =(y ij -y0)cos(α)-(x ij -x o )sin(α);

[0051] Where xij 、y ij They represent the x and y coordinates of the j-th microseismic event on the i-th day in the old coordinate system; α represents the clockwise angle between the new coordinate and the x-axis of the old coordinate system; x o y0 and y1 are the x and y coordinates of the origin A of the new coordinate system respectively; x′ ij , y′ ij represents the x and y coordinates of the j-th microseismic event on the i-th day in the new coordinate system.

[0052] As a preferred embodiment, in step (4), the method for determining the x-coordinate of the daily advancement position of the working face in the new coordinate system is as follows: select the eye B point under the working face as the starting point of the working face advancement, introduce the working face footage data, and calculate using the following formula:

[0053] x′ Bi =(x B -x0)cos(α)+(y B -y0)sin(α)±L i ;

[0054] Where x′ Bi represents the advancing position of the working face on day i; x B 、y B L is the coordinate of the selected cutting point B on the working surface; i Indicates the cumulative footage on the i-th day. When the advancement direction of the working face is consistent with the positive direction of the new coordinate x-axis, select "+" for calculation, otherwise select "-" for calculation.

[0055] Specifically, in step (5), the calculation formula for the strike distance of daily microseismic events from the working face advancement position is as follows:

[0056] d ij =x′ Bi -x′ ij ;

[0057] Where, d ij It represents the strike distance between the jth microseismic event on the i-th day and the advancing position of the working face.

[0058] Specifically, in step (6), the calculation formulas for the total microseismic energy and the microseismic frequency in each divided statistical area are as follows:

[0059] E n =e 1n +e 2n +e 3n +…+e mn ,

[0060] Q n =q 1n +q 2n +q3n +…+q mn ;

[0061] Where, E n is the total microseismic energy in each statistical area, i.e., the sub-area; Q n is the frequency of microseismic events in each statistical area, i.e., the sub-area; e in is the energy of the i-th microseismic event in the n-th partition, i = 1, 2, 3, ..., m; q in is the i-th microseismic event in the n-th partition, i = 1, 2, 3, …, m; n is the partition number.

[0062] As a preferred embodiment, in step (8), the total microseismic energy and microseismic frequency hazard levels are determined based on the total microseismic energy and microseismic frequency hazard standard values ​​determined by the working face mining conditions and monitoring and early warning indicators.

[0063] Example:

[0064] (1) By installing the SOS microseismic monitoring system, the mine microseismic monitoring system was used to collect multiple natural mine earthquake signals during the mining process of the 7301 working face. The location and energy of each natural mine earthquake signal were determined using known processing methods to obtain the microseismic data of the 7301 working face.

[0065] (2) Figure 1 As shown, point A (20401245.1220, 3916327.9279) is selected as the origin of the new coordinate system in the microseismic positioning base map. The x-axis of the new coordinate system is parallel to the advancing direction of the 7301 working face, and the clockwise angle α with the horizontal direction is 28.5°;

[0066] (3) Introducing the “7301 working face microseismic data”, using the coordinate transformation formula to determine the coordinate x′ of the microseismic event in the new coordinate system ij =(x ij -20401245.1220)cos(28.5°)+(y ij -3916327.9279)sin(28.5°),y′ ij =(y ij -3916327.9279)cos(28.5°)-(x ij -20401245.1220)sin(28.5°), where x ij 、y ij is the jth microseismic event on the i-th day of the 7301 working face;

[0067] (4) Select the B point (20402687.0159, 3917116.2743) of the lower cut of the working face as the starting point of the working face advancement;

[0068] (5) Introduce the "7301 working face advance data" to determine the daily working face advance position in the new coordinate system. The working face advance direction is opposite to the positive x direction in the new coordinate system, so the following formula uses "-" to calculate: x′ Bi =(x B -x0)cos(α)+(y B -y0)sin(α)-L i =(20402687.0159-20401245.1220)cos(28.5°)+(3917116.2743-3916327.9279)sin(28.5°)-L i =1267.16+376.16-L i =1643.32-L i , where L i is the cumulative footage of the working face on day i;

[0069] (6) Figure 2 and Figure 3 As shown in the figure, based on the distribution of microseismic events, the mining earthquakes within 800 m before and after the advancement position of the 7301 working face were selected for statistics. The strike direction was divided into several zones with equal intervals of 10 m. The total energy and frequency of the mining earthquakes in each zone were calculated using the accumulation method. The calculation formula is as follows:

[0070] E n =e 1n +e 2n +e 3n +…+e mn ,

[0071] Q n =q 1n +q 2n +q 3n +…+q mn ;

[0072] E n is the total microseismic energy in each statistical area, i.e., the sub-area, in J; Q n is the frequency of microseismic events in each statistical area, i.e., the sub-area; e in is the energy of the i-th microseismic event in the n-th partition, in J, i = 1, 2, 3, ..., m; q in is the frequency of the i-th microseismic event in the n-th partition, i = 1, 2, 3, …, m; n is the partition number;

[0073] (7) With the distance from the advancing position as the horizontal coordinate, the total energy and frequency of microseismic events in each statistical area, i.e., each subarea, as the vertical coordinate, and the advancing position as the coordinate origin, a curve of the total energy and frequency of microseismic events is drawn, as shown in the figure: Figure 4 As shown;

[0074] (8) Combined with the microseismic early warning index of the 7301 working face, the total energy of the partition is 3×10 5 J energy and frequency are divided into 100 microseismic events as the impact risk classification standard. Figure 4 It can be seen that there is an impact hazard within 160m ahead of the 7301 working face.

Claims

1. A microseismic statistical method for determining the range of risk of advanced impact on a working face, characterized in that: The steps include: (1) Use the mine microseismic monitoring system to collect natural microseismic signals during the mining process of the working face to determine the source location and source energy; (2) Select any coordinate point A(x0, y0) on the plan of the mining project as the origin of the new coordinate system, draw the new coordinate system, and the x-axis of the new coordinate system is parallel to the advancing direction of the working face; (3) Introducing microseismic data and processing it through the coordinate transformation formula to obtain the coordinates of the microseismic events in the new coordinate system; (4) Determine the starting coordinate B of the working face advancement, introduce the working face footage data, and obtain the x-coordinate of the daily advancement position of the working face in the new coordinate system; (5) Determine the strike distance of daily microseismic events from the working face advancement position; (6) Divide the statistical areas into equal intervals along the strike direction of the working face, and use the accumulation method to determine the total microseismic energy and microseismic frequency in each statistical area; (7) Using the distance from the working face advance position determined in step (5) as the horizontal coordinate and the total microseismic energy and microseismic frequency in each statistical area counted in step (6) as the vertical coordinate, draw a curve of the change of total microseismic energy and microseismic frequency; (8) Based on the curves of total microseismic energy and microseismic frequency obtained in step (7), the danger levels of total microseismic energy and microseismic frequency are divided to determine the range of the advanced impact danger zone.

2. A microseismic statistical method for determining the risk range of advanced impact of a working face according to claim 1, characterized in that: The method for determining the earthquake source position and earthquake source energy in the step (1) is as follows: by installing an SOS microseismic monitoring system in the coal mine, the SOS microseismic monitoring system includes an above-ground acquisition and recording device and a plurality of single-component probes installed underground, the plurality of single-component probes are installed on the anchor rods of the vertical tunnel floor, and the mine microseismic monitoring system is used to collect a plurality of natural mine earthquake signals during the working face mining process, and each natural mine earthquake signal is processed to obtain its corresponding mine earthquake source position and its energy.

3. A microseismic statistical method for determining the risk range of advanced impact of a working face according to claim 1 or 2, characterized in that: The x-axis of the new coordinate system drawn in step (2) is parallel to the advancing direction of the working surface and has a clockwise angle α with the x-axis of the old coordinate system.

4. The microseismic statistical method for determining the risk range of advanced impact of a working face according to claim 3, characterized in that: In step (3), the coordinate conversion formula is: x′ ij =(x ij -x o )cos(α)+(y ij -y0)sin(α), and' ij =(and ij -y0)cos(α)-(x ij -x o )sin(α); Where x ij 、y ij They represent the x and y coordinates of the j-th microseismic event on the i-th day in the old coordinate system; α represents the clockwise angle between the new coordinate and the x-axis of the old coordinate system; x o y0 and y1 are the x and y coordinates of the origin A of the new coordinate system respectively; x′ ij , y′ ij represents the x and y coordinates of the j-th microseismic event on the i-th day in the new coordinate system.

5. The microseismic statistical method for determining the risk range of advanced impact of a working face according to claim 4, characterized in that: In step (4), the x-coordinate of the daily advancement position of the working face in the new coordinate system is determined by selecting the eye B point under the working face as the starting point of the advancement of the working face, introducing the working face footage data, and calculating using the following formula: x′ Bi =(x B -x0)cos(α)+(y B -y0)sin(α)±L i ; Where x′ Bi represents the advancing position of the working face on day i; x B 、y B L is the coordinate of the selected cutting point B on the working surface; i Indicates the cumulative footage on the i-th day. When the advancing direction of the working face is consistent with the positive direction of the new coordinate x-axis, select "+" for calculation, otherwise select "-" for calculation.

6. The microseismic statistical method for determining the risk range of advance impact of a working face according to claim 5, characterized in that: In step (5), the calculation formula for the strike distance of daily microseismic events from the working face advancement position is as follows: d ij =x′ Bi -x′ ij ; Where, d ij It represents the strike distance between the jth microseismic event on the i-th day and the advancing position of the working face.

7. The microseismic statistical method for determining the risk range of advanced impact of a working face according to claim 6, characterized in that: In step (6), the calculation formulas for the total microseismic energy and the microseismic frequency in each divided statistical area are as follows: AND n =and 1n +e 2n +e 3n +…+and mn , Q n =q 1n +q 2n +q 3n +…+q mn ; Where, E n is the total microseismic energy in each statistical area, i.e., the sub-area; Q n is the frequency of microseismic events in each statistical area, i.e., the sub-area; e in is the energy of the i-th microseismic event in the n-th partition, i = 1, 2, 3, ..., m; q in is the i-th microseismic event in the n-th partition, i = 1, 2, 3, ..., m; n is the partition number.

8. The microseismic statistical method for determining the risk range of advanced impact of a working face according to claim 7, characterized in that: In the step (8), the total microseismic energy and microseismic frequency hazard levels are determined based on the working face mining conditions and the total microseismic energy and microseismic frequency hazard standard values ​​determined by monitoring and early warning indicators.

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